Hi: Noticed longer and longer drying times required for even small loads. Cleaned exhaust duct work with vacuum. Now machine tumbles but ZERO heat. Read on a group that likely culprit is non-resettable thermal cutoff. I don't own an ohm meter. Is this a $23.00 investment that solve the problem? Heating element is not broken; thermal fuse that was bad would not allow machine to even tumble. Any other advice? Thanks.